- a overview or summary about the VHF ham radio bands or amateur radio frequencies, the frequency allocations and their properties.

The VHF and UHF amateur radio allocations provide an interesting environment in which to operate. They are very different to the HF ham radio bands in their character, but this means that they provide a different challenge and a different area of interest within the hobby of amateur radio.

... amateur radio equipment for these bands is compact and widely available....

The VHF ham radio bands are very convenient to use. Antennas are small and amateur radio equipment for these bands is compact and widely available. This means that it is easy to set up and install a station in most areas, and many people even have a small ham radio station in their car.

Overview of VHF amateur radio bands

There is a number of different ham radio bands in the VHF portion of the radio spectrum. The actual allocations vary between one country and the next, and also the different radio regions. A summary of the allocations in the UK and the USA is given in the table below. It can be seen that some ham radio bands are allocated in the USA that are not available in the UK, and vice versa. However, the table gives a good indication of some of the allocations that are available around the globe. Of the bands available, 6 Metres and 2 Metres are possibly the most widely used and popular of the VHF ham radio allocations.

Amateur Radio Band

UK Allocation(MHz)

USA Allocation(MHz)

6 Metres

50.00 - 52.00

4 Metres

70.00 - 70.50

no allocation

2 Metres

144.00 - 146.00

144.00 - 148.00

1.25 Meters

no allocation

219.00 -220.00222.00 - 225.00

Each of the VHF amateur radio or ham radio bands has its own character. The propagation conditions combined with other factors including the size of the allocation, the availability of equipment and other similar factors means that the bands are sued for different purposes and the perform in different ways. Summaries for the different ham radio allocations are given below.

Six Metres (6 Meters)

UK Allocation(MHz)

USA Allocation(MHz)

50.00 - 52.00

50.00 - 54.00

This is the lowest of the VHF ham radio bands, being very close in frequency to the HF portion of the spectrum. At the peak of the sunspot cycle worldwide communication is possible, with long-distance stations being heard at very good strength. However, at either side of the peak when the ionosphere does not support propagation at these frequencies, distances are normally much shorter and the band takes on a feel more akin to that of the other VHF bands. Even under these conditions sporadic E gives the possibility of long-distance contacts.

Four Metres

UK Allocation(MHz)

USA Allocation(MHz)

70.00 - 70.50

No allocation

This ham radio band of frequencies is only available for amateur operation in a very limited number of countries of which the UK is one. (More details of the exact number to whom it is available can be found at www.70mhz.org.) However, it has been recognised that an amateur radio band on this frequency would be of great benefit to the amateur community and there is a possibility that in the future this allocation might become more widespread.

Since there are very few countries active on this ham radio band there is little commercial equipment available, and this results in most of the equipment being either home built or ex-mobile radio equipment (from taxis etc) that has been modified for the band. This makes 4 metres very interesting and appealing to many radio amateurs.

Propagation is very much like that found on Six Metres although normal ionospheric propagation is rarely experienced. Sporadic E does produce some excellent results when it appears, although contacts with other countries often have to be on a cross-band basis, with stations from outside the UK transmitting on either 50MHz or 28MHz.

Two Metres (2 Meters)

UK Allocation(MHz)

USA Allocation(MHz)

144.00 - 146.00

144.00 - 148.00

This is the most popular of the VHF and UHF ham radio bands, especially where FM local and mobile operation is concerned. There is a comprehensive set of 2m repeaters that together cover large parts of the UK and other countries where operation is envisaged. There is also a large level of data (packet radio) activity. For those interested in long-distance contacts there is also SSB and Morse activity which rises significantly during contests or when propagation conditions are good.

The ranges that can be achieved often depend very largely on the antenna, transmitter power and location. However, for most stations distances of at least 30 to 50km should be possible.

Those ham radio stations with high powers, good antennas and a good location will be able to reach much greater distances, especially when using SSB or Morse. When conditions on the band improve as a result of tropospheric propagation distances up to 1000km can be reached on occasions, and with sporadic E it is possible to make contacts over distances of some 2000km. However, this is the highest frequency ham radio band where sporadic E can be experienced.

Operation on FM is channelised. This makes it much easier to locate a particular frequency, especially when operating mobile. It also reduces the level of interference because channels are spaced such that a station on one channel does not interfere with one on the next. A system of channels spaced by 12.5kHz is replacing the previous one where channels were spaced by 25kHz.

1.25 Meters

UK Allocation(MHz)

USA Allocation(MHz)

No allocation

219.00 - 220.00222.00 - 225.00

This ham radio band is allocated in the USA but is not available in Europe. The bottom sector of the band (219.00 - 220.00) is available for fixed digital message forwarding systems only, whereas the top section is subject to the more usual restrictions and dependent on the licence class held by the licensee.

This ham radio band is popular for FM use. Its character is quite similar to that of two metres in terms of propagation. However, Sporadic E is seldom experienced on this band although it has been known.

Summary

The VHF ham radio allocations are ideal for local contacts and keeping in contact with local friends. However they are also ideal for many other applications and there is a large number of data transmissions that are sent on these frequencies. In addition to this they can also be used for DXing, their propagation characteristics often enabling contacts to be made over distances of 100 km and more, with distances of even 1500 km far from unknown. All these and many more aspects of these frequencies make these amateur radio or ham radio bands very interesting.